Kurt, are you still looking for some information on these springs? I think you and I are in the same boat. First let me tell you that I'm trying to download some pics but it won't let me.?? Anyway, I have some what I think are turn six springs. The parts were bought in the mid 80s by someone else and I bought them off him. All he knows is the numbers on the outside of the boxes. Carl Beck sent me a reply on classic datsun z.com about them. He said they will lower the car about one inch and are a progressive type spring that has no loss of ride characteristics. They sold for 139.95 in 1987. That's about all I know. I either pair them with a set of tokico illuminas or just use the illuminas with the stock springs and see if I like that. I'm just going for a weekend driver type car, 10/70 built Z. Oh, the boxes read 44-1513 12 on one and 44-1514 12.5 on the other. Let me know if these are like yours.

I believe Turn 6 springs were a product of and marketed by a company called Pacesetter. Check in the back of late '70s-early '80s copies of Car and Driver or Road & Track. They advertised quite a bit in those mags back in the day. The first set of sway bars I bought for my first 510 were Turn 6. Purchased new from IECO in Santa Monica in '82. I still have their catalog. IECO also advertised quite heavily in those same car mags back then. Turn 6 springs and sway bars were all painted bright yellow. Pretty sure the Turn 6 brand originated in SoCal and are named after the famous turn 6 at Riverside Raceway (RIP).